Laser devices provide output from an optical cavity when an included gain medium overcomes the cavity losses so that amplification via stimulated emission occurs. Lasers produce light over some natural bandwidth or range of frequencies, sometimes referred to as the gain bandwidth, which is largely determined by the laser gain medium and the optical cavity or resonant cavity of the laser. Saturable absorbers can be introduced into the optical cavity to provide variability in the cavity loss, which is typically nonlinear such that when a small number of photons are present there is a larger cavity loss than when a large number of photons are present. This allows Q-switching to occur if the excited upper state lifetime of the gain medium is sufficiently long to accumulate enough energy to overcome the cavity losses by forming a pulse. Alternatively, if the gain bandwidth and laser cavity simultaneously support a large optical bandwidth, a saturable absorber can initiate mode-locking or phase-locking of the laser by providing lower loss to a multiple longitudinal optical modes with a specific phase relationship within the laser resonant cavity. Mode-locked lasers can produce extremely short duration light pulses, on the order of picoseconds or femtoseconds. Moreover, passive, hybrid, or active mode-locking can be produced in a laser. Active mode-locking can be accomplished using an external signal to induce intra-cavity light modulation. Passive mode-locking, in contrast, involves incorporation of a structural element, such as a saturable absorber into the laser cavity to cause self-modulation of the light. In this manner, passive mode-locked lasers use the light in the cavity to cause a change in some intra-cavity element, which will then itself produce a change in the intra-cavity light. Saturable absorbers exhibit intensity-dependent transmission or reflection, and thus behave differently depending on the intensity of the light. For passive mode-locking in a laser, an ideal saturable absorber selectively absorbs low-intensity light, while transmitting or reflecting light which is of sufficiently high intensity, thereby acting as an optical gate. Thusfar, implementing passive mode-locked or Q-switched infrared lasers has been difficult, especially at infrared wavelengths, and a need remains for improved laser devices and implementation approaches, particularly for compact laser device structures.